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 共查询到19条相似文献,搜索用时 156 毫秒
1.
采用循环伏安法(CV)对离子液体Reline中三元CuCl2+InCl3+SeCl4体系和四元CuCl2+InCl3+GaCl3+SeCl4体系的电化学行为进行了研究。研究表明,In3+并入三元CIS(Cu-In-Se)薄膜体系和Ga3+并入四元CIGS(Cu-In-Ga-Se)薄膜体系均有两种途径:一是发生共沉积,二是直接还原。利用电感耦合等离子体发射光谱(ICP)和扫描电镜(SEM)对沉积电势、镀液温度和主盐浓度对CIGS薄膜组成、镀层表面形貌的影响进行了测试,结果表明通过工艺参数的选择可以控制Ga/(Ga+In)和CIGS薄膜组成并得到化学计量比为Cu1.00In0.78Ga0.27Se2.13的薄膜。  相似文献   

2.
用不同的预处理气氛制备了CeO2/γ-Al2O3载体以调节表面Ce的价态,并以Cu(CH3COO)2为前驱体制备了CuCeAl催化剂。XRD和H2-TPR的结果表明在还原气氛下处理的CeO2/γ-Al2O3载体具有更多的活性氧原子,因此相应的CuCeAl催化剂表面有更多分散态的Cu2+/Cu+物种。NO+CO反应的结果表明分散态的Cu2+/Cu+是NO转化的活性物质,而Cu0在低温下具有较好的N2选择性。因此,同时含有分散态Cu2+/Cu+和少量晶相Cu0的催化剂具有最好的催化性能。  相似文献   

3.
以醋酸铜(Cu(Ac)2)和正硅酸乙酯(TEOS)为前驱体,柠檬酸钠(Na3Cit)为配合剂,在室温下制备出物质的量之比nCu2+:nCit3-为1:1和1:2的两种透明稳定的Cu(Ⅱ)-Cit3--SiO2复合溶胶。以此为电解液,采用恒电位方法,在ITO阴极上直接制备出了CuxO-SiO2复合薄膜。CV(循环伏安)和XRD(X射线衍射)结果表明,在低过电位和高过电位分别得到Cu2O-SiO2和Cu/Cu2O-SiO2薄膜。XRD和EDX(X射线散射能谱)结果表明,相同沉积条件下,nCu2+:nCit3-为1:1溶胶中得到的薄膜中Cu含量较1:2溶胶中的高。薄膜在两种溶胶中的电化学形成机理不同,其原因在于溶胶中Cu(Ⅱ)存在的形式不同。CA(计时安培)和SEM(扫描电镜)结果一致表明,Cu和Cu2O在两种溶胶中的成核机理与电位有关,随着过电位增大,成核机理从三维连续成核逐渐转向瞬时成核。  相似文献   

4.
A new coordination complex [Cu(Ⅱ)(DETA)]3[Cr(CN)6]2·5H2O (DETA=diethylenetriamine) was synthesized, its crystal structure and magnetic properties were determined. The crystal crystallizes in monoclinic space group P21/c, with unit cell constants a=2.056 6(7) nm, b=1.440 7(5) nm, c=1.513 3(5) nm, β=95.996(6)°, and V=4.459(3) nm3, Z=4, Dc=1.499 g·cm-3, F(000)=2 060,μ(Mo )=1.936 mm-1, R1=0.052 3, wR2=0.106 2. The structure consists of a one-dimensional chain of [Cu(DETA)]2[Cr(CN)6]+ and binuclear [Cu(DETA)][Cr(CN)6]-. The coordination geometries around Cu2+ atoms are distorted square-based pyramidal and distorted square, respectively. Magnetism studies show that there are ferromagnetic interactions between Cu2+ and Cr3+ ions. CCDC: 272213.  相似文献   

5.
由H3nta(H3nta=nitriloriacetic acid)、Phen(Phen=1,10-phenanthroline)与Cu2+离子反应,合成标题配合物[Cu2(nta)(Phen)3]NO3·6H2O。该配合物的晶体属单斜晶系,空间群为P21/c。在配合物中,2个中心铜原子分别与配位原子构成变形八面体和变形三角双锥结构。晶体中结构单元通过分子间氢键和π-π堆积,形成了三维网络结构。TG分析结果表明标题配合物在194 ℃以下是稳定的。  相似文献   

6.
以CuSO4·5H2O和正硅酸乙酯为前驱体,配制了稳定透明的Cu2+-SiO2复合溶胶电解液。采用电化学-溶胶凝胶方法,在恒电位-0.9 V下得到Cu-SiO2复合膜,该复合薄膜分别在250和450℃的热处理后得到Cu2O-SiO2和CuO-SiO2复合薄膜。采用XRD、SEM/EDX和台阶仪表征了复合薄膜的组成、形貌和厚度;采用紫外-可见光谱和Z扫描技术研究了复合薄膜的线性和三阶非线性光学性能。结果表明Cu2O-SiO2和CuO-SiO2复合薄膜中的Cu含量、Cu的形态(如Cu2O、CuO)及Cu2O或CuO颗粒大小影响薄膜的光学带隙和三阶非线性光学性能,2种薄膜的光学带隙分别是2.67和2.54 eV,三阶非线性极化率χ(3)分别为2.31×10-6和1.36×10-6 esu。  相似文献   

7.
用X-射线测定了5,10,15,20-四(2-甲氧基苯基)卟啉合钴[TMOPCo(Ⅱ)]的晶体结构,实验表明,晶体属正交晶系,空间群Pbca, a=11.544(2), b=14.294(2), c=23.984(2)?,V=3957?3,Z=4, dc=1.329 g/cm3, μ(Cu)=39.45 cm-1, <  相似文献   

8.
水杨醛缩L-天冬氨酸过渡金属配合物的合成及表征   总被引:18,自引:0,他引:18  
合成了新的水杨醛天冬氨酸席夫碱配体及其铜、锌、钴、镍配合物,并利用元素分析、摩尔电导、热分析、红外光谱、电子光谱及顺磁共振等手段进行表征,确定配合物的化学组成为K[ML]·nH2O,式中L=C11H7NO, M=Cu2+、Zn2+、Co2+、Ni2+,相应地n=2、2、3、7/2。  相似文献   

9.
采用固相反应制备了Mg1-xCuxTiO3(0.00≤x≤0.20)微波介电陶瓷,研究CuO烧结助剂对MgTiO3陶瓷的微观结构和微波介电性能的影响。实验结果表明,CuO中的Cu2+离子会进入到MgTiO3晶格中并取代Mg2+,形成Mg1-xCuxTiO3固溶体。由于液相效应,适量的CuO可以促进MgTiO3陶瓷的致密化烧结,降低其烧结温度。Cu2+离子的A位取代会改变样品的TiO6八面体扭曲度。随着Cu2+离子含量的增加,会使MgTiO3陶瓷的结构稳定性降低。随着CuO含量的增加,晶粒的不均匀生长和液相的出现导致样品的品质因数(Qf)下降。同时,Mg1-xCuxTiO3陶瓷的相对密度、结构稳定性和平均共价度的降低也会恶化陶瓷的Qf值。样品的介电常数(εr)与离子极化率、杂相和TiO6八面体扭曲度相关。样品的谐振频率温度系数(τf)随TiO6八面体扭曲度的增加而减小。当x=0.08时,样品可在1 150℃实现致密化烧结,且τf值改善至-3.4×10-5-1。  相似文献   

10.
由Cu(Ⅱ)、2,2′-联吡啶(邻菲咯啉)与N-苯基亚氨基二乙酸在溶液中组装得到2个双核配合物[Cu2(L)2(2,2′-bipy)2]·8H2O (1)、[Cu2(L)2(phen)2]·2H2O (2)(H2L=N-苯基亚氨基二乙酸,2,2′-bipy=2,2′-联吡啶,phen=邻菲咯啉)。用元素分析、红外光谱、热重分析等进行了表征,并测定了其晶体结构。晶体结构表明,配合物1的晶体属三斜晶系,空间群P1;配合物2的晶体属单斜晶系,空间群P21/c。在这2个双核配合物中,中心铜离子的配位形式均为五配位的畸变四方锥构型,配体L中的N原子没有参与配位,而是采用1个羧基的1个氧原子与Cu2+离子螯合、另1个羧基上的1个氧原子以μ2-桥联的配位模式连接2个Cu2+离子。  相似文献   

11.
采用循环伏安法(CV)对离子液体Reline中三元CuCl2+InCl3+SeCl4体系和四元CuCl2+InCl3+GaCl3+SeCl4体系的电化学行为进行了研究。研究表明,In3+并入三元CIS(Cu-In-Se)薄膜体系和Ga3+并入四元CIGS(Cu-In-Ga-Se)薄膜体系均有两种途径:一是发生共沉积,二是直接还原。利用电感耦合等离子体发射光谱(ICP)和扫描电镜(SEM)对沉积电势、镀液温度和主盐浓度对CIGS薄膜组成、镀层表面形貌的影响进行了测试,结果表明通过工艺参数的选择可以控制Ga/(Ga+In)和CIGS薄膜组成并得到化学计量比为Cu1.00In0.78Ga0.27Se2.13的薄膜。  相似文献   

12.
《Analytical letters》2012,45(10):1587-1596
Chemically synthesized nanostructures possess well-defined domains with an interconnected network, which helps the carriers to bypass the other material in the solar cell while moving to their respective electrodes. In this work, CuInS2 films constituting CuInS2 nanotubes and nanoparticles were fabricated using a hot-injection chemical technique, followed by sulfurization. Structural and microstructural investigations reveal Cu2S nanoparticle formation at an early stage of growth of nanotubes, serving as possible catalyst sites for the subsequent anisotropic growth of the heterostructured hexagons. The crossover takes place over a number of intermediate stages. This sharing of the heterostructure by the hexagonal Cu2S and chalcopyrite CuInS2 minimizes the lattice distortion. The Cu2S- CuInS2 interface in the heterostructure acts as the nucleation center for CuInS2 nanotubes. Optical absorption and Raman spectroscopy studies reveal better optical properties for CuInS2 nanoparticles as compared to CuInS2 nanotubes. Compared to all other nanostructures, nanowires or nanotubes tend to provide single-crystalline nanograins for direct characterization. These nanoparticles, especially the nanotubes, can be used to form an interconnected network structure of p- and n-type materials in bulk heterojunctions providing the key to improve solar cell efficiencies.  相似文献   

13.
在室温下,以不同cCu/cIn的CuCl2和InCl3混合溶液作为阳离子前驱体,Na2S水溶液为硫源,利用连续离子层吸附反应法(SILAR)在玻璃基底上制备了CuInS2薄膜。XRD结果表明,当cCu2 /cIn3 在1 ̄1.5范围内均可形成具有黄铜矿结构的CuInS2薄膜。SEM观察到随cCu2 /cIn3 的升高,薄膜表面颗粒长大并出现团簇聚集。通过XPS测定薄膜表面的化学组成证明当cCu2 /cIn3 =1.25时,CuInS2薄膜接近其标准的化学计量组成。此时薄膜的吸收系数大于>104cm-1,禁带宽度Eg为1.45eV。  相似文献   

14.
A low cost spin coating route of fabricating CuInS2 polycrystalline thin films by reactive sin-tering method was put forward. The ink for spin coating was optimized by pre-reducing the precursor powders in hydrogen, which turned the nanoparticle precursor powders from mixed sulfides into a mixture of CuInS2 and Cu-In metal alloys. The results of scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Raman spectra showed that this optimization could highly improve the performance of CuInS2 polycrystalline thin films, including higher packing density, less impurity phases, and better quality. The en-ergy gap of optimized CuInS2 thin film was determined to be about 1.45 eV by absorption spectroscopy measurement.  相似文献   

15.
Hexagonal YMnO3 has a ferroelectric property with an optimal remanent polarization along the c-axis. The c-axis oriented YMnO3 thin films with a small leakage current were prepared by the sol-gel dipping method. The c-axis orientation of the films was promoted by the addition of diethanolamine to the Mn precursor solution. A heat treatment with multiple steps led to a dense film structure with fine grains. The dense structure resulted in the decrease of the leakage current. Furthermore, when the films were heat-treated in a vacuum, the leakage current became considerably small and the ferroelectricity of the YMnO3 thin films was observed even at room temperature.  相似文献   

16.
Bi-layered ferroelectric Bi3TiTaO9 (BTT) thin films with different thickness (ranging from 100 to 400 nm) were successfully fabricated on Pt(111)/TiO2/SiO2/(100)Si substrates using chemical solution deposition (CSD) technique at different annealing temperatures. The c-axis orientation of the films was affected by film thickness and process temperature. The thinner the film and the higher the process temperature, the higher the c-axis orientation. With the increase of film thickness, the stress decreased but the film roughness increased, which led to the decrease of c-axis orientation of films. BTT films annealed at 800°C were found to have much improved remament polarization (P r ) than that of films annealed at 650 and 750°C. The P r and coercive field (E c ) values were measured to be 2 μC/cm2 and 100 kV/cm, respectively. BTT films showed well-defined ferroelectric properties with grain size larger than 100 nm.  相似文献   

17.
(Y,Yb)MnO3 and HfO2 films were prepared using alkoxy-derived precursor solutions, and (Y,Yb)MnO3/HfO2/Si structures were fabricated. The thickness, surface uniformity and crystallinity of the HfO2 film affect the crystallization of Y0.5Yb0.5MnO3 films. The degree of c-axis orientation and crystallinity of the Y0.5Yb0.5MnO3 films were changed with preparation conditions of HfO2 films. It was difficult to obtain Y0.5Yb0.5MnO3 films with high crystallinity and high degree of c-axis orientation on the HfO2 films thinner than 10 nm. The degree of c-axis orientation and crystallinity of the Y0.5Yb0.5MnO3 films on HfO2 films were improved by using diluted HfO2 precursor solution in the case of 10 nm-thick HfO2 film. Following this, the capacitance-voltage (C-V) characteristics were improved.  相似文献   

18.
CuInS2 nanoparticles (NPs) usually take chalcopyrite-(CP) structure. Recently, CuInS2 NPs with pseudo-wurtzite (WZ) structure, which is thermodynamically less favored, have been synthesized. However, the formation mechanism of this metastable-phase has not been understood yet. In this report, the key issue of phase selectivity of CuInS2 (CIS) NPs has been investigated using various metal sources and ligands. Experimental results suggested that the crystalline structure and morphology of CIS NPs were decided by the stability of indium ligand complex; the active ligand reduces the precipitation rate of In2S3, resulting in pre-generation of Cu2S seed NPs. Crystallographic analogy and superionic conductivity of Cu2S remind us that the formation of WZ CIS NPs is attributed to the pre-generation of Cu2S seed NPs and the following cation exchange reaction. In order to confirm this hypothesis, Cu2-xS seed NPs with various structures have been annealed in indium-ligand solution. This experiment revealed that the crystalline structure of CIS NP was determined by that of pre-generation Cu2-xS NPs. Our results provide the important information for the phase control and synthesis of ternary chalcogenide NPs with a novel crystalline structure.  相似文献   

19.
Calcium modified lead titanate sol was synthesized using a soft solution processing, the so-called polymeric precursor method. In soft chemistry method, soluble precursors such as lead acetate trihydrate, calcium carbonate and titanium isopropoxide, as starting materials, were mixed in aqueous solution. Pb0.7Ca0.3TiO3 thin films were deposited on platinum-coated silicon and quartz substrates by means of the spinning technique. The surface morphology and crystal structure, dielectric and optical properties of the thin films were investigated. The electrical measurements were conducted on metal-ferroelectric-metal (MFM) capacitors. The typical measured small signal dielectric constant and dissipation factor at a frequency of 100 kHz were 299 and 0.065, respectively, for a thin film with 230 nm thickness annealed at 600°C for 2 h. The remanent polarization (2Pr) and coercive field (E c) were 32 C/cm2 and 100 kV/cm, respectively. Transmission spectra were recorded and from them, refractive index, extinction coefficient, and band gap energy were calculated. Thin films exhibited good optical transmissivity, and had optical direct transitions. The present study confirms the validity of the DiDomenico model for the interband transition, with a single electronic oscillator at 6.858 eV. The optical dispersion behavior of PCT thin film was found to fit well the Sellmeir dispersion equation. The band gap energy of the thin film, annealed at 600°C, was 3.56 eV. The results confirmed that soft solution processing provides an inexpensive and environmentally friendly route for the preparation of PCT thin films.  相似文献   

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